:root {
    --primary-color: #2b5cff;
    --secondary-color: #1a1a2e;
    --accent-color: #ff4757;
    --bg-color: #f8f9fa;
    --surface-color: #ffffff;
    --text-color: #2f3542;
    --text-light: #747d8c;
    --border-color: #dfe4ea;
    --shadow: 0 10px 30px rgba(0,0,0,0.05);
    --shadow-hover: 0 15px 40px rgba(0,0,0,0.1);
}

[data-theme="dark"] {
    --primary-color: #537aff;
    --secondary-color: #f8f9fa;
    --bg-color: #121212;
    --surface-color: #1e1e1e;
    --text-color: #e0e0e0;
    --text-light: #a0a0a0;
    --border-color: #333333;
    --shadow: 0 10px 30px rgba(0,0,0,0.3);
    --shadow-hover: 0 15px 40px rgba(0,0,0,0.5);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
}

body {
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    transition: background-color 0.3s, color 0.3s;
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
header {
    background: var(--surface-color);
    padding: 80px 20px;
    text-align: center;
    border-bottom: 1px solid var(--border-color);
    position: relative;
    overflow: hidden;
}

.header-title {
    font-size: 2.8rem;
    font-weight: 800;
    margin-bottom: 15px;
    color: var(--secondary-color);
}

.header-subtitle {
    font-size: 1.2rem;
    color: var(--text-light);
    max-width: 700px;
    margin: 0 auto;
}

/* Section */
.section {
    padding: 60px 0;
}

.section-title {
    font-size: 1.8rem;
    margin-bottom: 30px;
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--secondary-color);
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 10px;
}

.card {
    background: var(--surface-color);
    border-radius: 16px;
    padding: 30px;
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
    margin-bottom: 30px;
}

/* Table */
.data-table {
    width: 100%;
    border-collapse: collapse;
    margin: 20px 0;
    font-size: 1rem;
}
.data-table th, .data-table td {
    padding: 15px;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}
.data-table th {
    background-color: rgba(var(--primary-color-rgb), 0.05);
    font-weight: 600;
}
.polar-up { color: var(--accent-color); font-weight: bold; }
.polar-down { color: var(--primary-color); font-weight: bold; }

/* Interactive Stereonet */
.interactive-area {
    display: flex;
    flex-wrap: wrap;
    gap: 30px;
    align-items: flex-start;
}

.stereonet-container {
    flex: 1;
    min-width: 300px;
    background: #fff; /* Stereonet always white bg for visibility */
    border-radius: 50%;
    box-shadow: 0 0 0 5px var(--surface-color), 0 0 20px rgba(0,0,0,0.1);
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
}

canvas {
    border-radius: 50%;
    background-color: #fff;
    cursor: crosshair;
}

.controls-container {
    flex: 1;
    min-width: 300px;
}

.station-list {
    list-style: none;
}
.station-item {
    padding: 15px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    margin-bottom: 10px;
    cursor: pointer;
    transition: 0.2s;
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.station-item:hover, .station-item.active {
    border-color: var(--primary-color);
    background: rgba(43, 92, 255, 0.05);
}

.btn {
    display: inline-block;
    padding: 10px 20px;
    border-radius: 8px;
    background: var(--primary-color);
    color: white;
    text-decoration: none;
    font-weight: bold;
    border: none;
    cursor: pointer;
    transition: 0.2s;
}
.btn:hover {
    background: #1e45c7;
}

.form-input {
    width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    background: var(--surface-color);
    color: var(--text-color);
    font-size: 0.95rem;
    transition: border-color 0.2s;
}
.form-input:focus {
    outline: none;
    border-color: var(--primary-color);
}

.theme-btn {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: var(--surface-color);
    color: var(--text-color);
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    cursor: pointer;
    z-index: 100;
}

/* Alerts */
.alert {
    padding: 20px;
    border-left: 4px solid var(--primary-color);
    background: rgba(43, 92, 255, 0.05);
    border-radius: 0 8px 8px 0;
    margin: 20px 0;
}
.alert-title {
    font-weight: bold;
    color: var(--primary-color);
    margin-bottom: 5px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.img-responsive {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
    border: 1px solid var(--border-color);
}