/* ========== CSS Variables ========== */
:root {
    --primary-color: #1e40af;
    --secondary-color: #10b981;
    --accent-color: #f59e0b;
    --danger-color: #ef4444;
    --dark-bg: #0f172a;
    --light-bg: #f8fafc;
    --card-bg: #ffffff;
    --text-dark: #1e293b;
    --text-light: #64748b;
    --border-color: #e2e8f0;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.07);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
}

body.dark-mode {
    --light-bg: #0f172a;
    --card-bg: #1e293b;
    --text-dark: #f1f5f9;
    --text-light: #cbd5e1;
    --border-color: #334155;
}

/* ========== Global Styles ========== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--light-bg);
    color: var(--text-dark);
    line-height: 1.6;
    transition: background-color 0.3s, color 0.3s;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ========== Header ========== */
.header {
    background-color: var(--card-bg);
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 100;
    border-bottom: 2px solid var(--border-color);
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 20px;
}

.logo h1 {
    font-size: 1.8rem;
    color: var(--primary-color);
}

.nav {
    display: flex;
    gap: 2rem;
    align-items: center;
}

.nav-link {
    text-decoration: none;
    color: var(--text-dark);
    font-weight: 500;
    transition: color 0.3s;
    border-bottom: 2px solid transparent;
    padding-bottom: 5px;
}

.nav-link:hover {
    color: var(--primary-color);
    border-bottom-color: var(--primary-color);
}

.header-controls {
    display: flex;
    gap: 1rem;
    align-items: center;
}

.dark-mode-btn,
.share-btn {
    background: none;
    border: none;
    font-size: 1.2rem;
    cursor: pointer;
    padding: 0.5rem;
    border-radius: 50%;
    transition: background-color 0.3s;
}

.dark-mode-btn:hover,
.share-btn:hover {
    background-color: var(--light-bg);
}

/* Hamburger Menu */
.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 5px;
    z-index: 101;
    padding: 0.5rem;
    border-radius: 8px;
    transition: all 0.3s ease;
}

.hamburger:hover {
    background-color: var(--light-bg);
}

.hamburger span {
    width: 25px;
    height: 3px;
    background-color: var(--text-dark);
    border-radius: 3px;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    transform-origin: center;
}

.hamburger.active span:nth-child(1) {
    transform: rotate(45deg) translate(10px, 10px);
}

.hamburger.active span:nth-child(2) {
    opacity: 0;
    transform: translateX(-10px);
}

.hamburger.active span:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -7px);
}

/* ========== Main Content ========== */
.main {
    min-height: 90vh;
    padding: 2rem 0;
}

.section {
    display: none;
    animation: fadeIn 0.3s ease-in;
}

.section-active {
    display: block;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes slideDown {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes pulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.7;
    }
}

@keyframes glow {
    0%, 100% {
        box-shadow: var(--shadow);
    }
    50% {
        box-shadow: 0 0 20px rgba(30, 64, 175, 0.4);
    }
}

.section h2 {
    font-size: 2.5rem;
    margin-bottom: 2rem;
    color: var(--primary-color);
    text-align: center;
}

/* ========== Home Section ========== */
.hero {
    text-align: center;
    margin-bottom: 3rem;
    padding: 2rem;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    border-radius: 15px;
    box-shadow: var(--shadow-lg);
}

.hero h2 {
    font-size: 3rem;
    color: white;
    margin-bottom: 1rem;
}

.hero p {
    font-size: 1.2rem;
    margin-bottom: 1rem;
    opacity: 0.9;
}

.hero blockquote {
    font-style: italic;
    font-size: 1.1rem;
    margin: 1.5rem 0;
    padding: 1rem;
    border-right: 4px solid rgba(255, 255, 255, 0.5);
    opacity: 0.95;
}

/* Stats */
.stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.stat-card {
    background-color: var(--card-bg);
    padding: 2rem;
    border-radius: 12px;
    text-align: center;
    box-shadow: var(--shadow);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    border: 2px solid transparent;
    position: relative;
    overflow: hidden;
}

.stat-card::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -50%;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle, rgba(30, 64, 175, 0.1) 0%, transparent 70%);
    transition: all 0.3s ease;
    z-index: 0;
}

.stat-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-color);
}

.stat-card:hover::before {
    top: 0;
    right: 0;
}

.stat-card h3 {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.stat-card p {
    color: var(--text-light);
    font-size: 1rem;
}

/* Progress Bar */
.progress-container {
    background-color: var(--card-bg);
    padding: 1.5rem;
    border-radius: 10px;
    margin-bottom: 2rem;
    box-shadow: var(--shadow);
}

.progress-container p {
    margin-bottom: 1rem;
    font-weight: 600;
}

.progress-bar {
    width: 100%;
    height: 10px;
    background-color: var(--border-color);
    border-radius: 10px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--secondary-color), var(--accent-color));
    transition: width 0.3s;
}

/* Daily Quote */
.daily-quote {
    background-color: var(--card-bg);
    padding: 2rem;
    border-radius: 10px;
    border-left: 5px solid var(--primary-color);
    box-shadow: var(--shadow);
    text-align: center;
}

.daily-quote h3 {
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.daily-quote p {
    font-style: italic;
    color: var(--text-light);
    font-size: 1.1rem;
}

/* ========== Tasks Section ========== */
.add-task-form {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
    background-color: var(--card-bg);
    padding: 1.5rem;
    border-radius: 10px;
    box-shadow: var(--shadow);
}

.add-task-form input,
.add-task-form select {
    flex: 1;
    min-width: 150px;
    padding: 0.75rem;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    background-color: var(--light-bg);
    color: var(--text-dark);
    font-family: inherit;
    transition: all 0.3s ease;
}

.add-task-form input:focus,
.add-task-form select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(30, 64, 175, 0.1);
    background-color: var(--card-bg);
}

.filter-buttons {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.filter-btn {
    padding: 0.6rem 1.8rem;
    background-color: transparent;
    border: 2px solid var(--border-color);
    border-radius: 25px;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    color: var(--text-dark);
    font-weight: 600;
    position: relative;
    overflow: hidden;
}

.filter-btn::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    background: var(--primary-color);
    border-radius: 50%;
    transform: translate(-50%, -50%);
    transition: width 0.3s, height 0.3s;
    z-index: -1;
}

.filter-btn.active {
    background-color: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.filter-btn:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(30, 64, 175, 0.2);
}

.tasks-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.task-item {
    background-color: var(--card-bg);
    padding: 1.5rem;
    border-radius: 10px;
    box-shadow: var(--shadow);
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-left: 5px solid var(--accent-color);
    transition: transform 0.3s, box-shadow 0.3s;
}

.task-item.high {
    border-left-color: var(--danger-color);
    background-color: rgba(239, 68, 68, 0.05);
}

.task-item.medium {
    border-left-color: var(--accent-color);
}

.task-item.low {
    border-left-color: var(--secondary-color);
}

.task-item.completed {
    opacity: 0.6;
}

.task-item.completed .task-title {
    text-decoration: line-through;
}

.task-item:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.task-info {
    flex: 1;
}

.task-title {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 0.5rem;
}

.task-details {
    font-size: 0.9rem;
    color: var(--text-light);
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.task-actions {
    display: flex;
    gap: 0.5rem;
}

.task-btn {
    padding: 0.5rem 1rem;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    transition: all 0.3s;
    font-weight: 500;
}

.task-btn-check {
    background-color: var(--secondary-color);
    color: white;
}

.task-btn-check {
    position: relative;
    overflow: hidden;
}

.task-btn-check:hover {
    background-color: #059669;
    box-shadow: 0 4px 12px rgba(16, 185, 129, 0.3);
    transform: translateY(-1px);
}

.task-btn-check:active {
    transform: scale(0.98);
}

.task-btn-delete {
    position: relative;
    overflow: hidden;
}

.task-btn-delete:hover {
    background-color: #dc2626;
    box-shadow: 0 4px 12px rgba(220, 38, 38, 0.3);
    transform: translateY(-1px);
}

.task-btn-delete:active {
    transform: scale(0.98);
}

.task-btn-delete {
    background-color: var(--danger-color);
    color: white;
}

.task-btn-delete:hover {
    background-color: #dc2626;
}

/* ========== Schedule Section ========== */
.add-schedule-form {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
    background-color: var(--card-bg);
    padding: 1.5rem;
    border-radius: 10px;
    box-shadow: var(--shadow);
}

.add-schedule-form input,
.add-schedule-form select {
    flex: 1;
    min-width: 150px;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 5px;
    background-color: var(--light-bg);
    color: var(--text-dark);
    font-family: inherit;
}

.schedule-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
}

.schedule-day {
    background-color: var(--card-bg);
    border-radius: 10px;
    overflow: hidden;
    box-shadow: var(--shadow);
}

.schedule-day-header {
    background-color: var(--primary-color);
    color: white;
    padding: 1rem;
    font-weight: 600;
    text-align: center;
}

.schedule-items {
    padding: 1rem;
}

.schedule-item {
    padding: 1rem;
    background-color: var(--light-bg);
    border-radius: 5px;
    margin-bottom: 0.5rem;
    border-right: 3px solid var(--secondary-color);
}

.schedule-item-time {
    font-weight: 600;
    color: var(--primary-color);
    margin-bottom: 0.3rem;
}

.schedule-item-subject {
    color: var(--text-dark);
    font-size: 0.95rem;
}

/* ========== Notes Section ========== */
.add-note-form {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    margin-bottom: 2rem;
    background-color: var(--card-bg);
    padding: 1.5rem;
    border-radius: 10px;
    box-shadow: var(--shadow);
}

.add-note-form input,
.add-note-form textarea,
.add-note-form select {
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 5px;
    background-color: var(--light-bg);
    color: var(--text-dark);
    font-family: inherit;
}

.add-note-form textarea {
    resize: vertical;
    min-height: 120px;
}

.notes-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1.5rem;
}

.note-card {
    padding: 1.5rem;
    border-radius: 12px;
    box-shadow: var(--shadow);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
    border: 1px solid rgba(255, 255, 255, 0.5);
}

.note-card::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: linear-gradient(45deg, transparent 30%, rgba(255, 255, 255, 0.1) 50%, transparent 70%);
    transform: translate(0, 0);
    transition: all 0.3s ease;
}

.note-card.yellow {
    background-color: #fef3c7;
    color: #78350f;
}

.note-card.blue {
    background-color: #dbeafe;
    color: #1e3a8a;
}

.note-card.green {
    background-color: #dcfce7;
    color: #166534;
}

.note-card.pink {
    background-color: #fbcfe8;
    color: #831843;
}

.note-card.purple {
    background-color: #e9d5ff;
    color: #6b21a8;
}

.note-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
}

.note-title {
    font-weight: 600;
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
}

.note-content {
    margin-bottom: 1rem;
    white-space: pre-wrap;
    word-wrap: break-word;
}

.note-actions {
    display: flex;
    gap: 0.5rem;
    justify-content: flex-end;
}

.note-btn {
    padding: 0.4rem 0.8rem;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 0.9rem;
    transition: all 0.3s;
}

.note-btn-pin {
    background-color: rgba(0, 0, 0, 0.1);
}

.note-btn-delete {
    background-color: rgba(239, 68, 68, 0.2);
    color: var(--danger-color);
}

/* ========== Files Section ========== */
.file-upload-area {
    background-color: var(--card-bg);
    border: 2px dashed var(--primary-color);
    border-radius: 10px;
    padding: 3rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s;
    margin-bottom: 2rem;
}

.file-upload-area:hover {
    background-color: var(--light-bg);
    border-color: var(--secondary-color);
}

.file-upload-area p {
    color: var(--text-light);
    font-size: 1.1rem;
}

.files-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 1.5rem;
}

.file-item {
    background-color: var(--card-bg);
    padding: 1.5rem;
    border-radius: 12px;
    box-shadow: var(--shadow);
    text-align: center;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    border: 2px solid transparent;
}

.file-item:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
    border-color: var(--secondary-color);
}

.file-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.file-name {
    font-weight: 600;
    word-break: break-all;
    margin-bottom: 0.5rem;
}

.file-size {
    color: var(--text-light);
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

.file-actions {
    display: flex;
    gap: 0.5rem;
    justify-content: center;
}

.file-btn {
    padding: 0.5rem 1rem;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    transition: all 0.3s;
    font-weight: 500;
}

.file-btn-download {
    background-color: var(--secondary-color);
    color: white;
    transition: all 0.3s ease;
}

.file-btn-download:hover {
    background-color: #059669;
    box-shadow: 0 4px 12px rgba(16, 185, 129, 0.3);
    transform: translateY(-1px);
}

.file-btn-delete {
    background-color: var(--danger-color);
    color: white;
    transition: all 0.3s ease;
}

.file-btn-delete:hover {
    background-color: #dc2626;
    box-shadow: 0 4px 12px rgba(220, 38, 38, 0.3);
    transform: translateY(-1px);
}

/* ========== Exams Section ========== */
.add-exam-form {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    margin-bottom: 2rem;
    background-color: var(--card-bg);
    padding: 1.5rem;
    border-radius: 10px;
    box-shadow: var(--shadow);
}

.add-exam-form input,
.add-exam-form textarea {
    padding: 0.75rem;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    background-color: var(--light-bg);
    color: var(--text-dark);
    font-family: inherit;
    transition: all 0.3s ease;
}

.add-exam-form input:focus,
.add-exam-form textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(30, 64, 175, 0.1);
}

.exams-list {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.exam-card {
    background-color: var(--card-bg);
    padding: 1.5rem;
    border-radius: 12px;
    box-shadow: var(--shadow);
    border-left: 5px solid var(--danger-color);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
}

.exam-card::before {
    content: '';
    position: absolute;
    top: 0;
    right: 0;
    width: 4px;
    height: 100%;
    background: linear-gradient(180deg, var(--accent-color), var(--danger-color));
    opacity: 0;
    transition: opacity 0.3s ease;
}

.exam-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.exam-card:hover::before {
    opacity: 1;
}

.exam-subject {
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.exam-details {
    display: flex;
    flex-wrap: wrap;
    gap: 1.5rem;
    margin-bottom: 1rem;
    color: var(--text-light);
    font-size: 0.95rem;
}

.exam-detail-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.exam-notes {
    background-color: var(--light-bg);
    padding: 1rem;
    border-radius: 8px;
    margin-bottom: 1rem;
    color: var(--text-dark);
    border-right: 3px solid var(--secondary-color);
    white-space: pre-wrap;
}

.exam-actions {
    display: flex;
    gap: 0.75rem;
    justify-content: flex-end;
}

.exam-btn {
    padding: 0.6rem 1.2rem;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-weight: 600;
    transition: all 0.3s ease;
    font-size: 0.9rem;
}

.exam-btn-delete {
    background-color: rgba(239, 68, 68, 0.1);
    color: var(--danger-color);
    border: 1px solid var(--danger-color);
}

.exam-btn-delete:hover {
    background-color: var(--danger-color);
    color: white;
    transform: scale(1.05);
}

.exam-countdow {
    font-size: 0.85rem;
    color: var(--danger-color);
    font-weight: 600;
    margin-bottom: 0.5rem;
}

/* ========== Timer Section ========== */
.timer-container {
    background-color: var(--card-bg);
    padding: 3rem;
    border-radius: 15px;
    box-shadow: var(--shadow-lg);
    text-align: center;
    max-width: 500px;
    margin: 0 auto;
}

.timer-display {
    font-size: 5rem;
    font-weight: bold;
    color: var(--primary-color);
    margin-bottom: 1rem;
    font-family: 'Courier New', monospace;
}

.timer-type {
    font-size: 1.5rem;
    color: var(--text-light);
    margin-bottom: 2rem;
}

.timer-controls {
    display: flex;
    gap: 1rem;
    justify-content: center;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.timer-settings {
    display: flex;
    gap: 2rem;
    justify-content: center;
    flex-wrap: wrap;
}

.timer-settings label {
    display: block;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.timer-settings input {
    width: 80px;
    padding: 0.5rem;
    border: 1px solid var(--border-color);
    border-radius: 5px;
    background-color: var(--light-bg);
    color: var(--text-dark);
    text-align: center;
}

/* ========== Contact Section ========== */
.contact-form {
    background-color: var(--card-bg);
    padding: 2rem;
    border-radius: 10px;
    box-shadow: var(--shadow);
    max-width: 600px;
    margin: 0 auto 2rem;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.contact-form input,
.contact-form textarea {
    padding: 1rem;
    border: 1px solid var(--border-color);
    border-radius: 5px;
    background-color: var(--light-bg);
    color: var(--text-dark);
    font-family: inherit;
}

.contact-form textarea {
    resize: vertical;
    min-height: 150px;
}

.social-links {
    display: flex;
    gap: 1.5rem;
    justify-content: center;
    flex-wrap: wrap;
}

.social-links a {
    padding: 0.75rem 1.5rem;
    background-color: var(--primary-color);
    color: white;
    text-decoration: none;
    border-radius: 8px;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-weight: 600;
    box-shadow: var(--shadow);
    position: relative;
    overflow: hidden;
}

.social-links a::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: rgba(255, 255, 255, 0.2);
    transition: left 0.3s ease;
}

.social-links a:hover::before {
    left: 100%;
}

.social-links a svg {
    width: 20px;
    height: 20px;
}

.social-whatsapp {
    background: linear-gradient(135deg, #25d366, #20ba5a) !important;
}

.social-whatsapp:hover {
    background: linear-gradient(135deg, #20ba5a, #1aa952) !important;
    transform: translateY(-3px);
    box-shadow: 0 8px 16px rgba(37, 211, 102, 0.3);
}

.social-facebook {
    background: linear-gradient(135deg, #1877f2, #0a66c2) !important;
}

.social-facebook:hover {
    background: linear-gradient(135deg, #0a66c2, #094ab5) !important;
    transform: translateY(-3px);
    box-shadow: 0 8px 16px rgba(24, 119, 242, 0.3);
}

.social-instagram {
    background: linear-gradient(135deg, #e1306c, #fd1d1d, #f77737, #fcaf45) !important;
}

.social-instagram:hover {
    background: linear-gradient(135deg, #fd1d1d, #f77737, #fcaf45, #e1306c) !important;
    transform: translateY(-3px);
    box-shadow: 0 8px 16px rgba(225, 48, 108, 0.3);
}

/* ========== Footer ========== */
.footer {
    background-color: var(--card-bg);
    color: var(--text-dark);
    text-align: center;
    padding: 2rem;
    border-top: 2px solid var(--border-color);
    margin-top: 3rem;
}

.footer p {
    margin: 0.5rem 0;
    color: var(--text-light);
}

/* ========== Buttons ========== */
.btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-weight: 600;
    transition: all 0.3s;
    font-family: inherit;
}

.btn-primary {
    background-color: var(--primary-color);
    color: white;
}

.btn-primary:hover {
    background-color: #1e3a8a;
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(30, 64, 175, 0.3);
}

.btn-secondary {
    background-color: var(--border-color);
    color: var(--text-dark);
}

.btn-secondary:hover {
    background-color: #cbd5e1;
}

/* ========== Modal ========== */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    z-index: 1000;
    justify-content: center;
    align-items: center;
}

.modal-content {
    background-color: var(--card-bg);
    padding: 2rem;
    border-radius: 15px;
    box-shadow: var(--shadow-lg);
    max-width: 500px;
    width: 90%;
    position: relative;
}

.reminder-modal {
    text-align: center;
}

.reminder-modal h2 {
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.reminder-content p {
    font-size: 1.3rem;
    margin-bottom: 1.5rem;
    color: var(--text-dark);
}

.close-btn {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: none;
    border: none;
    font-size: 2rem;
    cursor: pointer;
    color: var(--text-dark);
}

.reminder-modal .btn {
    margin: 0.5rem;
}

/* ========== Toast Notification ========== */
.toast {
    position: fixed;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    background-color: var(--primary-color);
    color: white;
    padding: 1rem 2rem;
    border-radius: 5px;
    box-shadow: var(--shadow-lg);
    z-index: 2000;
    opacity: 0;
    transition: opacity 0.3s;
    pointer-events: none;
}

.toast.show {
    opacity: 1;
    pointer-events: auto;
}

/* ========== Responsive Design ========== */
@media (max-width: 768px) {
    .hamburger {
        display: flex;
    }

    .header .container {
        flex-wrap: wrap;
    }

    .nav {
        display: none;
        position: absolute;
        top: 100%;
        right: 0;
        flex-direction: column;
        background-color: var(--card-bg);
        width: 100%;
        gap: 0;
        box-shadow: var(--shadow-lg);
        z-index: 99;
        animation: slideDown 0.3s ease;
        border-radius: 0 0 12px 12px;
        overflow: hidden;
    }

    .nav.active {
        display: flex;
    }

    .nav-link {
        padding: 1rem 1.5rem;
        border: none;
        border-bottom: 1px solid var(--border-color);
        text-align: right;
        transition: all 0.2s ease;
        position: relative;
    }

    .nav-link:hover {
        background-color: var(--light-bg);
        padding-right: 2rem;
        color: var(--primary-color);
    }

    .header-controls {
        order: -1;
    }

    .hero h2 {
        font-size: 2rem;
    }

    .section h2 {
        font-size: 1.8rem;
    }

    .timer-display {
        font-size: 3.5rem;
    }

    .add-task-form,
    .add-schedule-form,
    .add-note-form {
        flex-direction: column;
    }

    .add-task-form input,
    .add-task-form select,
    .add-schedule-form input,
    .add-schedule-form select,
    .add-note-form input,
    .add-note-form select,
    .add-note-form textarea {
        width: 100%;
    }

    .stats {
        grid-template-columns: repeat(2, 1fr);
    }

    .filter-buttons {
        flex-direction: column;
    }

    .filter-btn {
        width: 100%;
    }

    .task-item {
        flex-direction: column;
        align-items: flex-start;
    }

    .task-actions {
        width: 100%;
        margin-top: 1rem;
    }

    .task-btn {
        flex: 1;
    }

    .timer-controls {
        flex-direction: column;
    }

    .timer-controls .btn {
        width: 100%;
    }

    .toast {
        width: 90%;
        left: 50%;
        transform: translateX(-50%);
    }
}

@media (max-width: 480px) {
    .header {
        padding: 1rem 0;
    }

    .logo h1 {
        font-size: 1.5rem;
    }

    .hero {
        padding: 1rem;
    }

    .hero h2 {
        font-size: 1.5rem;
    }

    .hero blockquote {
        font-size: 1rem;
    }

    .stats {
        grid-template-columns: 1fr;
    }

    .stat-card h3 {
        font-size: 2rem;
    }

    .timer-display {
        font-size: 2.5rem;
    }

    .notes-grid {
        grid-template-columns: 1fr;
    }

    .schedule-grid {
        grid-template-columns: 1fr;
    }
}