:root {
    color-scheme: light;
    --bg: #ffffff;
    --panel: #ffffff;
    --text: #111827;
    --muted: #6b7280;
    --line: #e5e7eb;
    --primary: #111827;
    --primary-hover: #0b1220;
    --primary-soft: #f3f4f6;
    --error: #b91c1c;
    --shadow: 0 20px 50px rgba(15, 23, 42, 0.08);
}

:root[data-theme="dark"] {
    color-scheme: dark;
    --bg: #0b1220;
    --panel: #101a2e;
    --text: #e8edf6;
    --muted: #9fb0d0;
    --line: #2a3d5f;
    --primary: #7c3aed;
    --primary-hover: #8b5cf6;
    --error: #ef4444;
    --shadow: 0 20px 50px rgba(0, 0, 0, 0.35);
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    min-height: 100vh;
    background: var(--bg);
    color: var(--text);
    font-family: "Pretendard", "Noto Sans KR", sans-serif;
    /* 모든 프런트엔드 페이지 공통 기본 30px (어르신 사용성). */
    font-size: 30px;
    line-height: 1.4;
}

:root[data-theme="dark"] body {
    background: radial-gradient(circle at top left, #1b2a49, var(--bg) 45%);
}

.login-page {
    min-height: 100vh;
    display: grid;
    place-items: center;
    padding: 24px 16px;
}

.login-card {
    width: min(80vw, 960px);
    max-width: 100%;
    background: var(--panel);
    border: 1px solid var(--line);
    border-radius: 16px;
    padding: 28px 28px 32px;
    box-shadow: 0 1px 0 rgba(17, 24, 39, 0.04);
}

:root[data-theme="dark"] .login-card {
    box-shadow: var(--shadow);
}

.login-card h1 {
    margin: 0 0 12px;
    font-size: 60px;
    line-height: 1.15;
    font-weight: 800;
    letter-spacing: -0.03em;
}

.login-card p {
    margin: 0 0 20px;
    color: var(--muted);
}

form {
    display: grid;
    gap: 12px;
}

label {
    display: grid;
    gap: 6px;
    font-size: 40px;
}

input {
    width: 100%;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: #eff6ff;
    color: var(--text);
    font-size: 30px;
    line-height: 1.25;
    padding: 14px 16px;
}

:root[data-theme="dark"] input {
    background: color-mix(in oklab, var(--panel) 96%, #000 4%);
}

.signup-credential-box {
    margin: 20px 0;
    padding: 16px;
    border-radius: 12px;
    border: 1px solid var(--line);
    background: #f9fafb;
}

.signup-credential-line {
    margin: 0 0 16px;
    font-size: 30px;
}

.signup-credential-line:last-child {
    margin-bottom: 0;
}

.signup-credential-label {
    display: block;
    color: var(--muted);
    font-weight: 600;
    margin-bottom: 6px;
}

.signup-credential-value {
    display: block;
    font-size: 30px;
    word-break: break-all;
    padding: 12px 14px;
    border-radius: 10px;
    background: #eff6ff;
    border: 1px solid var(--line);
    color: var(--text);
}

.signup-warning {
    color: var(--error);
    font-size: 30px;
    margin: 16px 0 20px;
}

.login-primary-link {
    display: block;
    width: 100%;
    padding: 16px 18px;
    border-radius: 10px;
    border: 0;
    background: var(--primary);
    color: #ffffff;
    font-weight: 600;
    font-size: 30px;
    text-align: center;
    text-decoration: none;
    box-sizing: border-box;
}

.login-primary-link:hover {
    background: var(--primary-hover);
}

button {
    border: 0;
    border-radius: 10px;
    background: var(--primary);
    color: white;
    font-weight: 600;
    font-size: 40px;
    line-height: 1.2;
    padding: 16px 18px;
    cursor: pointer;
}

button:hover {
    background: var(--primary-hover);
}

button:active {
    transform: translateY(1px);
}

.login-signup-link {
    display: block;
    width: 100%;
    margin-top: 10px;
    padding: 16px 18px;
    border-radius: 10px;
    border: 1px solid var(--line);
    background: var(--panel);
    color: var(--text);
    font-weight: 600;
    font-size: 30px;
    text-align: center;
    text-decoration: none;
    box-sizing: border-box;
}

.login-signup-link:hover {
    background: var(--primary-soft);
    border-color: var(--muted);
}

:root[data-theme="dark"] .login-signup-link:hover {
    background: color-mix(in oklab, var(--panel) 85%, #000 15%);
}

:root[data-theme="dark"] button:hover {
    filter: brightness(1.08);
}

.error-box {
    border: 1px solid color-mix(in oklab, var(--error) 45%, var(--line));
    color: #991b1b;
    border-radius: 10px;
    padding: 10px 12px;
    background: #fef2f2;
    margin-bottom: 12px;
}

:root[data-theme="dark"] .error-box {
    border-color: color-mix(in oklab, var(--error) 60%, var(--line));
    color: #fecaca;
    background: #2b1320;
}

.error-text {
    color: #b91c1c;
}

:root[data-theme="dark"] .error-text {
    color: #fca5a5;
}