:root {
    --bg-dark: #07111f;
    --bg-mid: #13233a;
    --panel: rgba(10, 17, 30, 0.92);
    --text: #e2e8f0;
    --muted: #9fb0c7;
    --border: rgba(255, 255, 255, 0.08);
    --accent: #60a5fa;
    --accent-green: #22c55e;
    --accent-purple: #8b5cf6;
    --error: #f87171;
    --success: #4ade80;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: Arial, sans-serif;
}

/* Page layout */
html, body {
    height: 100%;
}

body {
    min-height: 100vh;
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
    background:
        radial-gradient(circle at 20% 20%, rgba(255, 255, 255, 0.16), transparent 20%),
        radial-gradient(circle at 80% 15%, rgba(125, 211, 252, 0.14), transparent 22%),
        radial-gradient(circle at 70% 80%, rgba(139, 92, 246, 0.16), transparent 24%),
        linear-gradient(135deg, #020617 0%, #07111f 45%, #111827 100%);
    padding: 20px;
    overflow-x: hidden;
    overflow-y: auto;
    color: var(--text);
}

#starfield {
    position: fixed;
    inset: 0;
    width: 100%;
    height: 100%;
    z-index: 0;
    pointer-events: none;
}

body::before {
    content: "";
    position: fixed;
    inset: 0;
    background:
        radial-gradient(circle at top left, rgba(74, 222, 128, 0.10), transparent 28%),
        radial-gradient(circle at bottom right, rgba(59, 130, 246, 0.12), transparent 34%);
    animation: pulseGlow 8s ease-in-out infinite alternate;
    pointer-events: none;
    z-index: 0;
}

body::after {
    content: "";
    position: fixed;
    width: clamp(80px, 10vw, 110px);
    height: clamp(80px, 10vw, 110px);
    right: clamp(4%, 6vw, 8%);
    top: clamp(6%, 8vh, 12%);
    border-radius: 50%;
    background: radial-gradient(circle at 35% 35%, #ffffff 0%, #dbeafe 25%, #94a3b8 55%, #475569 100%);
    box-shadow: 0 0 45px rgba(255, 255, 255, 0.25), 0 0 90px rgba(191, 219, 254, 0.18);
    opacity: 0.9;
    z-index: 0;
    pointer-events: none;
}

/* Main card */
.page {
    position: relative;
    z-index: 1;
    width: 100%;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px 0;
}

.auth-card {
    width: min(100%, 450px);
    max-width: 100%;
    background: var(--panel);
    padding: clamp(24px, 5vw, 40px) clamp(18px, 4vw, 30px);
    border-radius: 20px;
    box-shadow: 0 0 0 1px rgba(255, 255, 255, 0.06), 0 20px 45px rgba(0, 0, 0, 0.35);
    border: 1px solid var(--border);
    backdrop-filter: blur(10px);
}

/* Switch buttons */
.auth-switch {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 12px;
    margin-bottom: 24px;
}

.switch-button {
    border: none;
    background: transparent;
    color: var(--muted);
    font-size: 18px;
    font-weight: 600;
    cursor: pointer;
    transition: 0.3s ease;
}

.switch-button.active,
.switch-button:hover {
    color: #f8fafc;
    text-shadow: 0 0 10px rgba(96, 165, 250, 0.35);
}

.divider {
    width: 1px;
    height: 20px;
    background: rgba(255, 255, 255, 0.2);
}

/* Message box */
.message-box {
    min-height: 22px;
    margin-bottom: 16px;
    font-size: 14px;
    text-align: center;
    color: var(--text);
}

.message-box.success {
    color: var(--success);
}

.message-box.error {
    color: var(--error);
}

/* Form styles */
.auth-form {
    display: none;
    flex-direction: column;
    gap: 16px;
}

.auth-form.active-form {
    display: flex;
}

.field-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.field-group label {
    font-weight: 600;
    color: var(--text);
}

.field-group input {
    padding: 12px 14px;
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: 10px;
    font-size: 15px;
    outline: none;
    color: #f8fafc;
    background: rgba(255, 255, 255, 0.04);
    transition: border-color 0.3s ease, box-shadow 0.3s ease, transform 0.2s ease;
}

.field-group input::placeholder {
    color: #8ba0bb;
}

.field-group input:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(96, 165, 250, 0.2);
    transform: translateY(-1px);
}

.helper-text {
    color: var(--muted);
    font-size: 13px;
    line-height: 1.4;
}

/* Button */
.auth-button {
    margin-top: 6px;
    padding: 13px;
    border: none;
    border-radius: 10px;
    background: linear-gradient(135deg, #2563eb, var(--accent-green), var(--accent-purple));
    background-size: 200% 200%;
    color: #ffffff;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
    animation: gradientShift 4s ease infinite;
}

.auth-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 24px rgba(37, 99, 235, 0.28);
}

@keyframes pulseGlow {
    from {
        opacity: 0.65;
        transform: scale(1);
    }
    to {
        opacity: 1;
        transform: scale(1.04);
    }
}

@keyframes gradientShift {
    0% {
        background-position: 0% 50%;
    }
    50% {
        background-position: 100% 50%;
    }
    100% {
        background-position: 0% 50%;
    }
}

@media (max-width: 700px) {
    body {
        padding: 16px;
        align-items: flex-start;
    }

    .page {
        min-height: auto;
        padding: 12px 0;
        align-items: flex-start;
    }

    .auth-card {
        width: 100%;
    }
}

@media (max-width: 500px) {
    body {
        padding: 12px;
    }

    .auth-switch {
        gap: 8px;
        margin-bottom: 18px;
    }

    .switch-button {
        font-size: 16px;
    }

    .field-group input {
        padding: 11px 12px;
        font-size: 14px;
    }

    .auth-button {
        padding: 12px;
        font-size: 15px;
    }

    .helper-text {
        font-size: 12px;
    }
}