:root {
    --primary-color: #4a90e2;
    --secondary-color: #5cb85c;
    --background-color: #f8f9fa;
    --text-color: #343a40;
    --border-color: #dee2e6;
    --shadow-color: rgba(0,0,0,0.1);
    --success-color: #28a745;
    --hover-color: #357abd;
    --container-bg: #fff;
    --input-bg: #fff;
}

[data-theme="dark"] {
    --primary-color: #64b5f6;
    --secondary-color: #81c784;
    --background-color: #1a1a1a;
    --text-color: #e0e0e0;
    --border-color: #404040;
    --shadow-color: rgba(0,0,0,0.3);
    --success-color: #4caf50;
    --hover-color: #90caf9;
    --container-bg: #2d2d2d;
    --input-bg: #3d3d3d;
}

body {
    font-family: 'Segoe UI', 'Arial', sans-serif;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    background-color: var(--background-color);
    color: var(--text-color);
    padding: 20px;
    transition: all 0.3s ease;
}

.container {
    background-color: var(--container-bg);
    border-radius: 15px;
    box-shadow: 0 8px 16px var(--shadow-color);
    padding: 40px;
    text-align: center;
    width: 90%;
    max-width: 800px;
    transition: all 0.3s ease;
}

.container:hover {
    transform: translateY(-2px);
}

h1 {
    color: var(--primary-color);
    font-size: 2.5em;
    margin-bottom: 30px;
    text-shadow: 1px 1px 2px var(--shadow-color);
}

.theme-toggle {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 1000;
}

#darkModeToggle {
    background: transparent;
    border: 2px solid var(--border-color);
    border-radius: 50%;
    width: 40px;
    height: 40px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-color);
    transition: all 0.3s ease;
}

#darkModeToggle:hover {
    transform: scale(1.1);
    border-color: var(--primary-color);
}

.stats-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    margin: 30px 0;
}

.stat-box {
    background-color: var(--container-bg);
    border: 1px solid var(--border-color);
    border-radius: 10px;
    padding: 20px;
    text-align: center;
    transition: all 0.3s ease;
}

.stat-box:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 15px var(--shadow-color);
}

.stat-box i {
    font-size: 24px;
    color: var(--primary-color);
    margin-bottom: 10px;
}

.control-panel {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
    justify-content: center;
    align-items: center;
    margin: 30px 0;
}

.search-box {
    display: flex;
    gap: 10px;
    align-items: center;
}

#searchInput {
    padding: 10px 15px;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    font-size: 1em;
    background-color: var(--input-bg);
    color: var(--text-color);
    transition: all 0.3s ease;
    width: 250px;
}

#searchInput:focus {
    border-color: var(--primary-color);
    outline: none;
}

#readings {
    width: 90%;
    max-width: 700px;
    margin: 30px auto;
    border: 1px solid var(--border-color);
    border-radius: 10px;
    padding: 25px;
    font-size: 1em;
    line-height: 1.8;
    background-color: var(--container-bg);
}

.action-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: 15px;
    justify-content: center;
    margin: 30px 0;
}

.reading-day {
    margin: 15px 0;
    padding: 20px;
    border-radius: 8px;
    transition: all 0.3s ease;
    background-color: var(--container-bg);
    border: 1px solid var(--border-color);
}

.reading-day:not(.past):first-of-type {
    background-color: #f0f7ff;
    padding: 25px;
    border-radius: 10px;
    box-shadow: 0 4px 8px var(--shadow-color);
    font-size: 1.3em;
    border-left: 5px solid var(--primary-color);
}

.reading-day.past {
    font-size: 0.95em;
    opacity: 0.8;
    background-color: #f8f9fa;
}

.progress-bar {
    width: 100%;
    height: 25px;
    background-color: #e9ecef;
    border-radius: 15px;
    margin: 20px 0;
    overflow: hidden;
    box-shadow: inset 0 1px 3px var(--shadow-color);
}

.progress-bar-fill {
    height: 100%;
    background: linear-gradient(45deg, var(--primary-color), var(--secondary-color));
    border-radius: 15px;
    transition: width 0.5s ease-in-out;
}

#progress {
    margin: 20px 0;
    font-size: 1.2em;
}

#progress-value {
    color: var(--success-color);
    font-weight: bold;
}

.options {
    margin: 25px 0;
    padding: 15px;
    background-color: #f8f9fa;
    border-radius: 8px;
}

select#duration {
    padding: 10px 20px;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    font-size: 1em;
    margin: 0 10px;
    cursor: pointer;
    transition: all 0.3s ease;
}

select#duration:hover {
    border-color: var(--primary-color);
}

button {
    padding: 12px 24px;
    margin: 10px;
    border: none;
    border-radius: 8px;
    background-color: var(--primary-color);
    color: white;
    font-size: 1em;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 2px 4px var(--shadow-color);
}

button:hover {
    background-color: var(--hover-color);
    transform: translateY(-2px);
    box-shadow: 0 4px 8px var(--shadow-color);
}

#showPastDaysButton, #showFutureDaysButton {
    background-color: var(--secondary-color);
    margin: 10px 5px;
}

#showPastDaysButton:hover, #showFutureDaysButton:hover {
    background-color: #4a9d4a;
}

#resetButton {
    background-color: #dc3545;
}

#resetButton:hover {
    background-color: #c82333;
}

input[type="checkbox"] {
    appearance: none;
    -webkit-appearance: none;
    width: 22px;
    height: 22px;
    border: 2px solid var(--border-color);
    border-radius: 5px;
    margin: 0 10px;
    cursor: pointer;
    position: relative;
    transition: all 0.3s ease;
}

input[type="checkbox"]:checked {
    background-color: var(--success-color);
    border-color: var(--success-color);
}

input[type="checkbox"]:checked::after {
    content: '✓';
    position: absolute;
    color: white;
    font-size: 16px;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}

input[type="checkbox"]:hover {
    border-color: var(--primary-color);
}

label {
    padding: 8px;
    margin: 0 15px;
    font-size: 1.1em;
    cursor: pointer;
}

#bibleLink {
    display: inline-block;
    font-size: 1.8em;
    color: var(--primary-color);
    background-color: #f0f8ff;
    padding: 15px 30px;
    border-radius: 10px;
    margin: 20px 0;
    text-decoration: none;
    transition: all 0.3s ease;
    box-shadow: 0 2px 4px var(--shadow-color);
}

#bibleLink:hover {
    background-color: var(--primary-color);
    color: white;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px var(--shadow-color);
}

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

.reading-day {
    animation: fadeIn 0.5s ease-out;
}