* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/* Color Variables */
:root {
    --border: #8ebfcd;
    --card-bg: #f2fcfe;
    --card-line: #dae6eb;
    --primary-text: #172933;
    --button-light: #3c9fb7;
    --button-dark: #3582a2;
    --button-title: #ffffff;
    --button-border: #205469;
    --page-bg: #e7f8ff;
    --input-prefix-bg: #e8f3f9;
    --orange-600: #ea580c;
    --gray-600: #4b5563;
    --gray-200: #e5e7eb;
    --gray-100: #f3f4f6;
    --white: #ffffff;
    --success-color: #10b981;
}

/* Base Styles */
body {
    background-color: var(--page-bg);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
    font-family: 'Poppins', sans-serif;
    color: var(--primary-text);
    line-height: 1.6;
}

.app-container {
    width: 100%;
    max-width: 48rem; /* Slightly larger for video content */
    position: relative;
}

/* Workout Selector Styles */
.workout-selector {
    background-color: var(--card-bg);
    border-radius: 1.5rem;
    padding: 2rem;
    border: 1px solid var(--border);
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

.selector-title {
    font-size: 2rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 2rem;
    color: var(--primary-text);
}

.workout-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.workout-card {
    background-color: var(--white);
    border: 2px solid var(--card-line);
    border-radius: 1rem;
    padding: 1.5rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.workout-card:hover {
    border-color: var(--button-light);
    transform: translateY(-2px);
    box-shadow: 0 8px 25px -8px rgba(60, 159, 183, 0.3);
}

.workout-card:active {
    transform: translateY(0);
}

.workout-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
    display: block;
}

.workout-name {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--primary-text);
}

.workout-description {
    color: var(--gray-600);
    margin-bottom: 1rem;
    font-size: 0.9rem;
}

.workout-equipment {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    justify-content: center;
}

.equipment-tag {
    background-color: var(--input-prefix-bg);
    color: var(--primary-text);
    padding: 0.25rem 0.75rem;
    border-radius: 1rem;
    font-size: 0.75rem;
    font-weight: 500;
}

.back-to-selector {
    background-color: var(--button-light);
    color: var(--button-title);
    border: none;
    border-radius: 0.75rem;
    padding: 0.75rem 1.5rem;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    position: absolute;
    top: 1rem;
    left: 1rem;
    z-index: 10;
}

.back-to-selector:hover {
    background-color: var(--button-dark);
    transform: translateY(-1px);
}

@media (max-width: 768px) {
    .workout-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
    
    .workout-card {
        padding: 1.25rem;
    }
    
    .selector-title {
        font-size: 1.75rem;
        margin-bottom: 1.5rem;
    }
    
    .back-to-selector {
        position: static;
        width: 100%;
        margin-bottom: 1rem;
    }
}

/* Container/Card Styles */
.slide-container {
    background-color: var(--card-bg);
    border-radius: 1.5rem;
    overflow: hidden;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    border: 1px solid var(--border);
    position: relative;
    margin-bottom: 7rem; /* Space for navigation buttons */
}

/* Workout Type Header */
.workout-type-header {
    background: linear-gradient(135deg, var(--button-light), var(--button-dark));
    color: var(--button-title);
    padding: 1rem 1.5rem;
    text-align: center;
}

.workout-type-title {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 0.25rem;
}

.workout-type-description {
    font-size: 0.875rem;
    opacity: 0.9;
    margin: 0;
}

/* Header */
.exercise-header {
    padding: 1.5rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    border-bottom: 1px solid var(--card-line);
}

.icon-container {
    width: 3rem;
    height: 3rem;
    background: linear-gradient(to bottom, var(--button-light), var(--button-dark));
    border: 1px solid var(--button-border);
    border-radius: 9999px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.icon {
    height: 1.5rem;
    width: 1.5rem;
    color: var(--white);
}

.header-title {
    flex: 1;
}

.exercise-name {
    font-size: 1.25rem;
    line-height: 1.75rem;
    font-weight: 700;
    color: var(--primary-text);
    margin: 0;
}

.exercise-type {
    font-size: 0.875rem;
    color: var(--gray-600);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin: 0;
}

/* Slide */
.slide {
    display: none;
    width: 100%;
}

.slide.active {
    display: block;
}

/* Exercise Content */
.exercise-content {
    padding: 1.5rem;
}

/* Video Container */
.video-container {
    position: relative;
    width: 100%;
    margin-bottom: 1.5rem;
    background: #000;
    border-radius: 0.5rem;
    overflow: hidden;
    box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    border: 1px solid var(--card-line);
}

.video-wrapper {
    position: relative;
    padding-bottom: 56.25%; /* 16:9 aspect ratio */
    height: 0;
}

.video-wrapper iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border: none;
}

/* Exercise Controls */
.exercise-controls {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.control-group {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.75rem;
    background-color: var(--input-prefix-bg);
    border-radius: 0.5rem;
    border: 1px solid var(--card-line);
}

.control-label {
    font-weight: 400;
    color: var(--primary-text);
}

.control-value {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.control-btn {
    width: 36px;
    height: 36px;
    border: 1px solid var(--card-line);
    background: var(--card-bg);
    border-radius: 0.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.2s;
    box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
}

.control-btn:hover {
    background: var(--button-light);
    color: white;
    border-color: var(--button-light);
}

.control-display {
    min-width: 60px;
    text-align: center;
    font-weight: 600;
    color: var(--primary-text);
}

/* Buttons */
.button {
    padding: 0.75rem 2rem;
    border-radius: 9999px;
    font-weight: 600;
    font-family: 'Poppins', sans-serif;
    font-size: 1rem;
    cursor: pointer;
    position: relative;
    overflow: hidden;
    transition: all 0.3s ease;
    width: 100%;
}

.button-primary {
    background: linear-gradient(to bottom, var(--button-light), var(--button-dark));
    border: 1px solid var(--button-border);
    color: var(--button-title);
}

.button-primary:hover {
    background: linear-gradient(to bottom, var(--button-light), var(--button-light));
}

.button-text {
    position: relative;
    z-index: 10;
}

.button-primary .button-text {
    text-shadow: 0 1px 1px rgba(32, 84, 105, 0.95);
}

/* Button Overlays */
.button-overlay-1,
.button-overlay-2 {
    position: absolute;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    transition: opacity 0.3s;
}

.button-overlay-1 {
    background-color: rgba(255, 255, 255, 0.2);
    opacity: 0;
}

.button:hover .button-overlay-1 {
    opacity: 1;
}

.button-overlay-2 {
    opacity: 0.2;
    background: linear-gradient(to top, rgba(0, 0, 0, 0.3), transparent);
}

/* Timer Button */
.timer-button {
    margin-bottom: 1rem;
}

/* Complete Checkbox */
.complete-group {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.75rem;
    padding: 1rem;
    background-color: var(--input-prefix-bg);
    border-radius: 0.5rem;
    border: 1px solid var(--card-line);
    margin-top: 1rem;
}

.complete-checkbox {
    width: 20px;
    height: 20px;
    cursor: pointer;
}

.complete-label {
    font-weight: 600;
    cursor: pointer;
    user-select: none;
}

/* Progress Section */
.progress-section {
    padding: 1rem 1.5rem;
    border-top: 1px solid var(--card-line);
    background-color: var(--card-bg);
    position: relative;
}

.progress-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.5rem;
}

.progress-text {
    font-size: 0.875rem;
    color: var(--gray-600);
}

.progress-bar {
    height: 0.25rem;
    background-color: var(--gray-200);
    border-radius: 0.125rem;
    overflow: hidden;
}

.progress-fill {
    background-color: var(--button-light);
    height: 100%;
    transition: width 0.3s ease;
}

/* Navigation */
.navigation {
    position: fixed;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 1.5rem;
    z-index: 100;
}

.nav-btn {
    width: 3.5rem;
    height: 3.5rem;
    border-radius: 9999px;
    background: linear-gradient(to bottom, var(--button-light), var(--button-dark));
    border: 1px solid var(--button-border);
    color: var(--button-title);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.2s;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    position: relative;
    overflow: hidden;
}

.nav-btn:hover:not(:disabled) {
    background: linear-gradient(to bottom, var(--button-light), var(--button-light));
}

.nav-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.nav-btn svg {
    position: relative;
    z-index: 10;
}

/* Timer Modal */
.timer-modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    padding: 1rem;
}

.timer-content {
    background: var(--card-bg);
    padding: 2rem;
    border-radius: 1.5rem;
    text-align: center;
    max-width: 400px;
    width: 100%;
    border: 1px solid var(--border);
    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
}

.timer-content h2 {
    font-size: 1.5rem;
    margin-bottom: 1.5rem;
    color: var(--primary-text);
    font-weight: 700;
}

.timer-display {
    font-size: 3.5rem;
    font-weight: 700;
    color: var(--button-dark);
    margin-bottom: 2rem;
    font-variant-numeric: tabular-nums;
}

.timer-controls {
    display: flex;
    gap: 0.75rem;
    justify-content: center;
    flex-wrap: wrap;
}

.timer-btn {
    padding: 0.5rem 1.5rem;
    border-radius: 9999px;
    font-weight: 600;
    font-size: 0.875rem;
    cursor: pointer;
    transition: all 0.2s;
    font-family: 'Poppins', sans-serif;
}

.timer-btn:not(.close) {
    background: linear-gradient(to bottom, var(--button-light), var(--button-dark));
    border: 1px solid var(--button-border);
    color: var(--button-title);
}

.timer-btn:not(.close):hover {
    background: linear-gradient(to bottom, var(--button-light), var(--button-light));
}

.timer-btn.close {
    background: linear-gradient(to bottom, var(--card-bg), var(--card-bg));
    border: 1px solid var(--card-line);
    color: var(--primary-text);
}

.timer-btn.close:hover {
    background: linear-gradient(to bottom, var(--white), var(--gray-100));
}

/* Responsive Design */
@media (max-width: 768px) {
    .slide-container {
        margin-bottom: 6rem;
    }

    .exercise-content {
        padding: 1rem;
    }

    .exercise-header {
        padding: 1rem;
    }

    .exercise-name {
        font-size: 1.125rem;
    }

    .control-group {
        flex-direction: column;
        gap: 0.5rem;
        text-align: center;
    }

    .navigation {
        bottom: 1rem;
        gap: 1rem;
    }

    .nav-btn {
        width: 3rem;
        height: 3rem;
    }

    .timer-display {
        font-size: 3rem;
    }
}

@media (max-width: 480px) {
    .slide-container {
        margin-bottom: 5rem;
    }

    .exercise-name {
        font-size: 1rem;
    }

    .button {
        padding: 0.5rem 1.5rem;
        font-size: 0.875rem;
    }

    .timer-content {
        padding: 1.5rem;
    }

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